Generally, the arm roller is supported rotatably to the arm cam and its conventional construction is shown in FIG. 7, in which a support S integral with a center pin C having a threaded shaft T is fixed to an arm cam A by use of a nut N screwed with threaded shaft T, the center pin C carrying therearound an arm roller R having at the center a pin insertion bore H.
In this construction, however, the arm roller R, when subjected to a tensile force P from the line guided by the same, will cause a frictional force F which is given by the equation: EQU F=P.times..mu.,
where .mu. is a friction factor between the arm roller R and the center pin C. the friction force F increases in proportion to the intensity of tensile force P, thereby creating a problem in that the increasing friction force F will hinder smnooth rotation of arm roller R.
In other words, in the conventional reel construction as described above, the tensile force by the line acts on the center pin C perpendicularly to the center line thereof through the arm roller R. As a result, the frictional force F caused between the arm roller R and the center pin C applies a resistance against the rotation of arm roller R and increases as the tensile force P increases, thereby hindering smooth rotation of arm roller R.